Manipulating Nanostructure During High-Speed Casting of Glassy Metals

在玻璃金属高速铸造过程中操纵纳米结构

• 批准号: 1400964
• 负责人: Paul Steen
• 金额: $ 40万
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2018-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1400964&HistoricalAwards=false
• 关键词: Manipulating; Nanostructure; During; Speed; Casting

During processing, most metals such as iron or aluminum will solidify into an ordered atomic-scale crystalline structure. In contrast, if sufficiently hindered during the final stages of processing, solidified metals will lack atomic-scale order. In this study, a planar-flow casting process is used to produce a disordered structure known as glassy metal. Glassy metals often have favorable properties such as ultra-high strength for a glassy stainless steel. The favorable electromagnetic properties of the alloys under study are that they enable energy-savings in applications such as electric vehicle power systems, power harvesting from wind or photovoltaic sun farms and power distribution. Such properties can be further enhanced by incorporating fine features, or nanostructure. This study proposes a new approach to incorporating these fine features during planar flow casting. To be able to manufacture green-enabling products using a technique that itself has low carbon footprint represents a double benefit to society. As part of this project, community outreach will foster the interest of school children in science, technology, engineering and mathematics with a special focus aimed at encouraging high-school girls toward technical careers.The goal is to advance the ability to rapidly solidify thin metallic glass alloys continuously at speeds of meters per second, all while controlling in real-time the formation of nanocrystals. Control is sought of the extent to which crystallization occurs and where in the solidified product it occurs. At production speeds of meters per second, this represents unprecedented nanostructure control. The intellectual significance of this work relates to the non-equilibrium materials science of rapid transformations on the atomic scale in the presence of high thermal gradients. The approach will include experiments using a modified planar-flow casting machine, characterization of the product structure using X-ray diffraction and transmission electron microscopy, simulation of the temperature field within the material and substrate, and mathematical modeling of the metal-on-metal contacting event. The results of this effort will have impact on high speed non-equilibrium processing for materials other than metals as well.

在加工过程中，大多数金属（例如铁或铝）将凝固成有序的原子尺度结构结构。 相反，如果在加工的最后阶段受到足够的阻碍，固化金属将缺乏原子尺度的顺序。 在这项研究中，使用平面流式铸造过程来产生一种称为玻璃金属的无序结构。玻璃金属通常具有有利的特性，例如玻璃状不锈钢的超高强度。 所研究合金的有利电磁特性是，它们可以在电动汽车电动系统，风能或光伏太阳场和电源分布等应用中提供节能。可以通过合并精美的特征或纳米结构来进一步增强此类属性。 这项研究提出了一种在平面流铸造过程中纳入这些精美特征的新方法。 能够使用本身具有低碳足迹的技术制造绿色的产品对社会来说是双重好处。 作为该项目的一部分，社区外展将促进学童对科学，技术，工程和数学的兴趣，旨在鼓励高中女孩朝着技术职业迈进。其目标是促进能够以每秒的速度迅速巩固薄金属玻璃合金，同时以每秒的速度连续地控制Nananocrystals的形成。 寻求控制结晶的程度以及发生在凝固产物中的程度。在每秒米的生产速度下，这代表了前所未有的纳米结构控制。 这项工作的智力意义与高热梯度的存在下的非平衡材料科学有关原子量表的快速转化。 该方法将包括使用改良的平面流式铸造机的实验，使用X射线衍射和透射电子显微镜对产品结构的表征，材料和基板内温度场的模拟以及金属对金属接触事件的数学建模。这项工作的结果将影响金属以外的其他材料的高速非平衡处理。